vedomostiregmedРегуляторные исследования и экспертиза лекарственных средствRegulatory Research and Medicine Evaluation3034-30623034-3453Federal State Budgetary Institution ‘Scientific Centre for Expert Evaluation of Medicinal Products’ of the Ministry of Health of the Russian Federation (FSBI ‘SCEEMP’)10.30895/1991-2919-2022-12-4-455-467vedomostiregmed-505Research ArticleКОНТРОЛЬ КАЧЕСТВА ЛЕКАРСТВЕННЫХ СРЕДСТВQUALITY CONTROL OF MEDICINESОсобенности и практические аспекты определения радиохимической чистоты рецепторспецифичных препаратов лютеция-177 на примере [177Lu]Lu–PSMA-617Features and Practical Aspects of Radiochemical Purity Determination of Receptor-Specific Lu-177 Radiopharmaceuticals as Exemplified by [177Lu]Lu–PSMA-617https://orcid.org/0000-0003-4810-4346ЛаренковА. А.LarenkovA. A.

Ларенков Антон Алексеевич, канд. хим. наук

123098, Москва, Живописная ул., д. 46

Anton А. Larenkov, Cand. Sci. (Chem.)

123098, Moscow, Zhivopisnaya St., 46

anton.larenkov@gmail.comhttps://orcid.org/0000-0001-5249-8507МитрофановЮ. А.MitrofanovYu. A.Митрофанов Юрий Алексеевич

123098, Москва, Живописная ул., д. 46

Yury A. Mitrofanov

123098, Moscow, Zhivopisnaya St., 46

mitrofanoff.yura@yandex.ruhttps://orcid.org/0000-0002-7521-5976РахимовМ. Г.RakhimovM. G.Рахимов Марат Галиевич

123098, Москва, Живописная ул., д. 46

Marat G. Rakhimov

123098, Moscow, Zhivopisnaya St., 46

marat.rakhimov89@gmail.comФедеральное государственное бюджетное учреждение «Государственный научный центр Российской Федерации — Федеральный медицинский биофизический центр имени А.И. Бурназяна» Федерального медико-биологического агентства РоссииРоссияState Research Center – Burnasyan Federal Medical Biophysical Center of Federal Medical Biological AgencyRussian Federation202202112022124455467Copyright © Ларенков А.А., Митрофанов Ю.А., Рахимов М.Г., 20222022Ларенков А.А., Митрофанов Ю.А., Рахимов М.Г.Larenkov A.A., Mitrofanov Y.A., Rakhimov M.G.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.vedomostincesmp.ru/jour/article/view/505

Одним из основных критериев качества радиофармацевтических лекарственных препаратов (РФЛП), используемых в клинической практике, является радиохимическая чистота (РХЧ). Результаты анализа РХЧ зависят от используемой методики анализа, а также параметров детектирования, специфичных для конкретной аналитической системы. При анализе данных литературы по синтезу, фармацевтической разработке, доклиническим и клиническим исследованиям одного и того же РФЛП можно отметить существенные различия результатов определения величины РХЧ, что обуславливает актуальность тщательного выбора условий анализа и исследования их влияния на результат. Цель работы: сопоставление опубликованных ранее и разработанных нами методик анализа РХЧ препаратов 177Lu на примере [177Lu]Lu–PSMA-617 для определения радиохимических примесей, а также определение параметров аналитической системы, оказывающих существенное влияние на интерпретацию полученных результатов анализа. Материалы и методы: в качестве модели препарата использовали образцы [177Lu]Lu–PSMA-617 с объемной активностью 177Lu 150–4800 МБк/мл, содержащего 10–100 мкмоль/л прекурсора PSMA-617 и 30 ммоль/л натрия ацетата в качестве буферного раствора (pH 4,5). Контроль препаратов проводили методами высокоэффективной жидкостной хроматографии (ВЭЖХ) и тонкослойной хроматографии. Результаты: показано существенное влияние выбранной методики анализа на результаты оценки РХЧ [177Lu]Lu–PSMA-617. Профиль возможных радиохимических примесей требует применения методик ВЭЖХ-анализа с высокой разрешающей способностью. Выводы: разработанный и применяемый нами метод является достаточно эффективным. Продемонстрировано влияние параметров детектирующей системы, в частности длины проточной кюветы, ее внутреннего объема, а также средств обработки аналитического сигнала (параметры выделения пиков, сглаживания, вычитание/подавление шума) на результаты оценки РХЧ. Данный факт требует проведения процедур валидации с учетом особенностей конкретной аналитической системы, а также демонстрирует необходимость оценки межлабораторной прецизионности в рамках внедрения и верификации аналитических методик.

Radiochemical purity (RCP) is one of the key quality criteria for radiopharmaceuticals (RPs) used in clinical practice. The results of RCP measurements depend on the analytical technique, as well as detection parameters, which are specific to a particular analytical system. When reviewing literature data on the  synthesis, pharmaceutical development, preclinical and clinical trials of the same radiopharmaceutical by different authors, one may note significant variability in the RCP values obtained. Hence, it is important to carefully select analysis parameters and study their influence on the results. The aim of the study was to compare previously published and self-developed procedures for RCP analysis of 177Lu-RPs in terms of their efficiency in the  detection and quantification of possible radiochemical impurities, as well as to  determine the  analytical system parameters that have a  significant impact on the interpretation of the analysis results, using [177Lu]Lu–PSMA-617 as a case study. Materials and methods: the study used samples of [177Lu]Lu–PSMA-617 with a volume activity of lutetium-177 of 150–4800 MBq/mL, containing 10–100 µmol/L of the PSMA-617 precursor and 30 mmol/L of sodium acetate as a buffering solution (pH 4.5). The samples were tested by high-performance liquid chromatography (HPLC) and thin-layer chromatography in the conditions described in the literature and developed in the course of the work. Results: the study showed a significant influence of the chosen analytical procedure on the results of [177Lu]Lu–PSMA-617 RCP assessment. The profile of possible radiochemical impurities requires the use of high-resolution HPLC techniques. Conclusions: the analytical procedure developed and applied by the authors is quite effective. The results of RCP assessment are influenced by the detection system parameters, such as the length and inner diameter of the flow cell and the means of analytical signal processing (peak extraction parameters, smoothing parameters, and noise subtraction/suppression). This fact necessitates validation considering the characteristics of a particular analytical system and demonstrates the need to assess interlaboratory precision in the framework of the implementation and verification of analytical procedures.

радиофармпрепаратконтроль качестварадиохимическая чистотарадиохимические примесилютеций-177ВЭЖХPSMA-617radiopharmaceutical productquality controlradiochemical purityradiochemical impuritieslutetium-177HPLCPSMA-617Работа выполнена в рамках государственного задания ФМБА России (НИОКТР № 122031100121-4, руководитель — Ларенков А.А.).The research reported in this publication was carried out as part of a publicly funded research project and supported by the Federal Medical Biological Agency of Russia (R&D public accounting No. 122031100121-4, supervisor: A. Larenkov).ReferencesDolgin E. Radioactive drugs emerge from the shadows to storm the market. Nat Biotechnol. 2018;36(12):1125–7. https://doi.org/10.1038/nbt1218-1125Dolgin E. Radioactive drugs emerge from the shadows to storm the market. Nat Biotechnol. 2018;36(12):1125–7. https://doi.org/10.1038/nbt1218-1125Sgouros G, Bodei L, McDevitt MR, Nedrow JR. Radiopharmaceutical therapy in cancer: clinical advances and challenges. Nat Rev Drug Discov. 2020;19(9):589–608. https://doi.org/10.1038/s41573-020-0073-9Sgouros G, Bodei L, McDevitt MR, Nedrow JR. Radiopharmaceutical therapy in cancer: clinical advances and challenges. Nat Rev Drug Discov. 2020;19(9):589–608. https://doi.org/10.1038/s41573-020-0073-9Herrero Álvarez N, Bauer D, Hernández-Gil J, Lewis JS. Recent advances in radiometals for combined imaging and therapy in cancer. ChemMedChem. 2021;16(19): 2909–41. https://doi.org/10.1002/cmdc.202100135Herrero Álvarez N, Bauer D, Hernández-Gil J, Lewis JS. Recent advances in radiometals for combined imaging and therapy in cancer. ChemMedChem. 2021;16(19): 2909–41. https://doi.org/10.1002/cmdc.202100135Banerjee S, Pillai MRA, Russ Knapp FF. Lutetium-177 therapeutic radiopharmaceuticals: linking chemistry, radiochemistry, and practical applications. Chem Rev. 2015;115(8):2934–74. https://doi.org/10.1021/cr500171eBanerjee S, Pillai MRA, Russ Knapp FF. Lutetium-177 therapeutic radiopharmaceuticals: linking chemistry, radiochemistry, and practical applications. Chem Rev. 2015;115(8):2934–74. https://doi.org/10.1021/cr500171eHennrich U, Kopka K. Lutathera®: the first FDA- and EMA-approved radiopharmaceutical for peptide receptor radionuclide therapy. Pharmaceuticals. 2019;12(3):114. https://doi.org/10.3390/ph12030114Hennrich U, Kopka K. Lutathera®: the first FDA- and EMA-approved radiopharmaceutical for peptide receptor radionuclide therapy. Pharmaceuticals. 2019;12(3):114. https://doi.org/10.3390/ph12030114Kratochwil C, Fendler WP, Eiber M, Baum R, Bozkurt MF, Czernin J, et al. EANM procedure guidelines for radionuclide therapy with <sup>177</sup>Lu-labelled PSMA-ligands (<sup>177</sup>LuPSMA-RLT). Eur J Nucl Med Mol Imaging. 2019;46(12): 2536–44. https://doi.org/10.1007/s00259-019-04485-3Kratochwil C, Fendler WP, Eiber M, Baum R, Bozkurt MF, Czernin J, et al. EANM procedure guidelines for radionuclide therapy with <sup>177</sup>Lu-labelled PSMA-ligands (<sup>177</sup>LuPSMA-RLT). Eur J Nucl Med Mol Imaging. 2019;46(12): 2536–44. https://doi.org/10.1007/s00259-019-04485-3Ferdinandus J, Violet J, Sandhu S, Hofman MS. Prostate-specific membrane antigen theranostics: therapy with lutetium-177. Curr Opin Urol. 2018;28(2):197–204. https://doi.org/10.1097/mou.0000000000000486Ferdinandus J, Violet J, Sandhu S, Hofman MS. Prostate-specific membrane antigen theranostics: therapy with lutetium-177. Curr Opin Urol. 2018;28(2):197–204. https://doi.org/10.1097/mou.0000000000000486Emmett L, Willowson K, Violet J, Shin J, Blanksby A, Lee J. Lutetium <sup>177</sup>PSMA radionuclide therapy for men with prostate cancer: a review of the current literature and discussion of practical aspects of therapy. J Med Radiat Sci. 2017;64(1):52–60. https://doi.org/10.1002/jmrs.227Emmett L, Willowson K, Violet J, Shin J, Blanksby A, Lee J. Lutetium <sup>177</sup>PSMA radionuclide therapy for men with prostate cancer: a review of the current literature and discussion of practical aspects of therapy. J Med Radiat Sci. 2017;64(1):52–60. https://doi.org/10.1002/jmrs.227Chakraborty S, Vimalnath KV, Chakravarty R, Sarma HD, Dash A. Multidose formulation of readyto-use <sup>177</sup>Lu–PSMA-617 in a centralized radiopharmacy set-up. Appl Radiat Isot. 2018;139:91–7. https://doi.org/10.1016/j.apradiso.2018.04.033Chakraborty S, Vimalnath KV, Chakravarty R, Sarma HD, Dash A. Multidose formulation of readyto-use <sup>177</sup>Lu–PSMA-617 in a centralized radiopharmacy set-up. Appl Radiat Isot. 2018;139:91–7. https://doi.org/10.1016/j.apradiso.2018.04.033de Zanger RMS, Chan HS, Breeman WAP, de Blois E. Maintaining radiochemical purity of [<sup>177</sup>Lu]Lu–DOTA-PSMA-617 for PRRT by reducing radiolysis. J Radioanal Nucl Chem. 2019;321:285–91. https://doi.org/10.1007/s10967-019-06573-yde Zanger RMS, Chan HS, Breeman WAP, de Blois E. Maintaining radiochemical purity of [<sup>177</sup>Lu]Lu–DOTA-PSMA-617 for PRRT by reducing radiolysis. J Radioanal Nucl Chem. 2019;321:285–91. https://doi.org/10.1007/s10967-019-06573-yde Blois E, Chan HS, Konijnenberg M, de Zanger R, Breeman WAP. Effectiveness of quenchers to reduce radiolysis of (111)In- or (177)Lu-labelled methionine-containing regulatory peptides. Maintaining radiochemical purity as measured by HPLC. Curr Top Med Chem. 2013;12(23):2677–85. https://doi.org/10.2174/1568026611212230005de Blois E, Chan HS, Konijnenberg M, de Zanger R, Breeman WAP. Effectiveness of quenchers to reduce radiolysis of (111)In- or (177)Lu-labelled methionine-containing regulatory peptides. Maintaining radiochemical purity as measured by HPLC. Curr Top Med Chem. 2013;12(23):2677–85. https://doi.org/10.2174/1568026611212230005de Blois E, Chan HS, de Zanger R, Konijnenberg M, Breeman WAP. Application of single-vial ready-foruse formulation of <sup>111</sup>In- or <sup>177</sup>Lu-labelled somatostatin analogs. Appl Radiat Isot. 2014;85:28–33. https://doi.org/10.1016/j.apradiso.2013.10.023de Blois E, Chan HS, de Zanger R, Konijnenberg M, Breeman WAP. Application of single-vial ready-foruse formulation of <sup>111</sup>In- or <sup>177</sup>Lu-labelled somatostatin analogs. Appl Radiat Isot. 2014;85:28–33. https://doi.org/10.1016/j.apradiso.2013.10.023Mathur A, Prashant V, Sakhare N, Chakraborty S, Vimalnath KV, Mohan RK, et al. Bulk scale formulation of therapeutic doses of clinical grade ready-to-use <sup>177</sup>Lu-DOTA-TATE: the intricate radiochemistry aspects. Cancer Biother Radiopharm. 2017;32(7):266–73. https://doi.org/10.1089/cbr.2017.2208Mathur A, Prashant V, Sakhare N, Chakraborty S, Vimalnath KV, Mohan RK, et al. Bulk scale formulation of therapeutic doses of clinical grade ready-to-use <sup>177</sup>Lu-DOTA-TATE: the intricate radiochemistry aspects. Cancer Biother Radiopharm. 2017;32(7):266–73. https://doi.org/10.1089/cbr.2017.2208Chakraborty S, Chakravarty R, Shetty P, Vimalnath KV, Sen IB, Dash A. Prospects of medium specific activity (177)Lu in targeted therapy of prostate cancer using (177)Lu-labeled PSMA inhibitor. J Labelled Comp Radiopharm. 2016;59(9):364–71. https://doi.org/10.1002/jlcr.3414Chakraborty S, Chakravarty R, Shetty P, Vimalnath KV, Sen IB, Dash A. Prospects of medium specific activity (177)Lu in targeted therapy of prostate cancer using (177)Lu-labeled PSMA inhibitor. J Labelled Comp Radiopharm. 2016;59(9):364–71. https://doi.org/10.1002/jlcr.3414Wieczorek Villas Boas CA, Pereira Dias LA, Nakamura Matsuda MM, Bortoleti de Araújo E. Stability in the production and transport of 177Lu labelled PSMA. Brazilian J Radiat Sci. 2021;9(1):1–12. https://doi.org/10.15392/bjrs.v9i1.1619Wieczorek Villas Boas CA, Pereira Dias LA, Nakamura Matsuda MM, Bortoleti de Araújo E. Stability in the production and transport of 177Lu labelled PSMA. Brazilian J Radiat Sci. 2021;9(1):1–12. https://doi.org/10.15392/bjrs.v9i1.1619Martin S, Tönnesmann R, Hierlmeier I, Maus S, Rosar F, Ruf J, et al. Identification, characterization, and suppression of side products formed during the synthesis of [<sup>177</sup>Lu]Lu–PSMA-617. J Med Chem. 2021;64(8):4960–71. https://doi.org/10.1021/acs.jmedchem.1c00045Martin S, Tönnesmann R, Hierlmeier I, Maus S, Rosar F, Ruf J, et al. Identification, characterization, and suppression of side products formed during the synthesis of [<sup>177</sup>Lu]Lu–PSMA-617. J Med Chem. 2021;64(8):4960–71. https://doi.org/10.1021/acs.jmedchem.1c00045Zaknun JJ, Bodei L, Mueller-Brand J, Pavel ME, Baum RP, Hörsch D, et al. The joint IAEA, EANM, and SNMMI practical guidance on peptide receptor radionuclide therapy (PRRNT) in neuroendocrine tumours. Eur J Nucl Med Mol Imaging. 2013;40(5):800–16. https://doi.org/10.1007/s00259-012-2330-6Zaknun JJ, Bodei L, Mueller-Brand J, Pavel ME, Baum RP, Hörsch D, et al. The joint IAEA, EANM, and SNMMI practical guidance on peptide receptor radionuclide therapy (PRRNT) in neuroendocrine tumours. Eur J Nucl Med Mol Imaging. 2013;40(5):800–16. https://doi.org/10.1007/s00259-012-2330-6Кодина ГЕ, Малышева АО, Ларенков АА, Брускин АБ. Присутствие возможных примесей в радиофармацевтических лекарственных препаратах и методы их определения. Ведомости Научного центра экспертизы средств медицинского применения. Регуляторные исследования и экспертиза лекарственных средств. 2022;12(3):244–62. https://doi.org/10.30895/1991-2919-2022-12-3-244-262Kodina GE, Malysheva, AO, Larenkov AA, Bruskin AB. Possible impurities in radiopharmaceuticals and corresponding test methods. Vedomosti Nauchnogo tsentra ekspertizy sredstv meditsinskogo primeneniya. Regulyatornye issledovaniya i ekspertiza lekarstvennykh sredstv = Bulletin of the Scientific Centre for Expert Evaluation of Medicinal Products. Regulatory Research and Medicine Evaluation. 2022;12(3):244–62 (In Russ.) https://doi.org/10.30895/1991-2919-2022-12-3-244-262Mu L, Hesselmann R, Oezdemir U, Bertschi L, Blanc A, Dragic M, et al. Identification, characterization and suppression of side-products formed during the synthesis of high dose 68 GaDOTA-TATE. Appl Radiat Isot. 2013;76:63–9. https://doi.org/10.1016/j.apradiso.2012.07.022Mu L, Hesselmann R, Oezdemir U, Bertschi L, Blanc A, Dragic M, et al. Identification, characterization and suppression of side-products formed during the synthesis of high dose 68 GaDOTA-TATE. Appl Radiat Isot. 2013;76:63–9. https://doi.org/10.1016/j.apradiso.2012.07.022Larenkov AA, Maruk AYa, Kodina GE. Intricacies of the determination of the radiochemical purity of <sup>68</sup>Ga preparations: possibility of sorption of ionic <sup>68</sup>Ga species on reversed-phase columns. Radiochemistry. 2018;60: 625–33. https://doi.org/10.1134/S1066362218060103Larenkov AA, Maruk AYa, Kodina GE. Intricacies of the determination of the radiochemical purity of <sup>68</sup>Ga preparations: possibility of sorption of ionic <sup>68</sup>Ga species on reversed-phase columns. Radiochemistry. 2018;60: 625–33. https://doi.org/10.1134/S1066362218060103Maruk AYu, Larenkov A.A. Determination of ionic 68 Ga impurity in radiopharmaceuticals: major revision of radio-HPLC methods. J Radioanal Nucl Chem. 2020;323: 189–95. https://doi.org/10.1007/s10967-019-06964-1Maruk AYu, Larenkov A.A. Determination of ionic 68 Ga impurity in radiopharmaceuticals: major revision of radio-HPLC methods. J Radioanal Nucl Chem. 2020;323: 189–95. https://doi.org/10.1007/s10967-019-06964-1Liu S, Edwards DS. Bifunctional chelators for therapeutic lanthanide radiopharmaceuticals. Bioconjug Chem. 2001;12(1):7–34. https://doi.org/10.1021/bc000070vLiu S, Edwards DS. Bifunctional chelators for therapeutic lanthanide radiopharmaceuticals. Bioconjug Chem. 2001;12(1):7–34. https://doi.org/10.1021/bc000070vBreeman WAP. Practical aspects of labeling DTPA-and DOTA-peptides with <sup>90</sup>Y, <sup>111</sup>In, <sup>177</sup>Lu, <sup>68</sup>Ga for peptide-receptor scintigraphy and peptide-receptor radionuclide therapy in preclinical and clinical applications. University of New Mexico Health Sciences Center, College of Pharmacy; 2012. https://pharmacyce.unm.edu/program_information/freelessonfiles/vol16lesson5.pdfBreeman WAP. Practical aspects of labeling DTPA-and DOTA-peptides with <sup>90</sup>Y, <sup>111</sup>In, <sup>177</sup>Lu, <sup>68</sup>Ga for peptide-receptor scintigraphy and peptide-receptor radionuclide therapy in preclinical and clinical applications. University of New Mexico Health Sciences Center, College of Pharmacy; 2012. https://pharmacyce.unm.edu/program_information/freelessonfiles/vol16lesson5.pdfBreeman WAP, Chan SH, de Zanger RMS, Konijnenberg MK, de Blois E. Overview of development and formulation of <sup>177</sup>Lu-DOTA-TATE for PRRT. Curr Radiopharm. 2016;9(1):8–18. https://doi.org/10.2174/1874471008666150313111131Breeman WAP, Chan SH, de Zanger RMS, Konijnenberg MK, de Blois E. Overview of development and formulation of <sup>177</sup>Lu-DOTA-TATE for PRRT. Curr Radiopharm. 2016;9(1):8–18. https://doi.org/10.2174/1874471008666150313111131

The authors declare that there are no conflicts of interest present.